Estimates of Running Ground Reaction Force Parameters from Motion Analysis

Area of Science:

• Biomechanics
• Sports Science
• Human Movement Analysis

Background:

• Ground Reaction Force (GRF) measurements are standard for analyzing running mechanics.
• Kinematic (K) data from motion analysis offers a potentially more accessible alternative.
• Previous studies have explored the correlation between GRF and K data.

Purpose of the Study:

• To compare running mechanics parameters derived from GRF and K data.
• To assess the accuracy of estimating forces from kinematic data.
• To determine the feasibility of using motion analysis for running dynamics assessment.

Main Methods:

• Collected GRF and K data from participants running at speeds from 1.94 to 5.56 m/s.
• Utilized a force-instrumented treadmill and motion analysis system.
• Compared parameters at different sampling frequencies (900/300 Hz for GRF, 300/100 Hz for K).

Main Results:

• Vertical force peak, shape, and impulse showed high similarity between K and GRF methods.
• Contact time, flight time, and vertical stiffness (k_vert) from K aligned with GRF (<5% difference).
• Leg stiffness (k_leg) could not be accurately computed using kinematics.

Conclusions:

• Key vertical GRF parameters can be accurately computed from double differentiation of motion analysis data.
• This provides a viable, accessible alternative to instrumented treadmills for running analysis.
• The method is effective for determining temporal and kinetic running parameters.